Make ALT-X exit as originally intended.

src/syncterm/syncterm.c

@@ -1279,9 +1279,9 @@ int main(int argc, char **argv)
 				free(bbs);
 			}
 			bbs=NULL;
+			break;
 		}
-		else
-			bbs=NULL;
+		bbs=NULL;
 	}
 	uifcbail();
 #ifdef _WINSOCKAPI_